Uko of East Frisia was enrolled at the University of Cologne as a student in 1481.

Like his older brothers Enno I and Edzard I, Uko had a share in the government of the County of East Frisia.

He played a role during the Saxon feud that ravaged Frisia between 1498 and 1517.

Together with his brother Edzard I, he swore allegiance to the Duke of Saxony who had been appointed as hereditary governor of the entire Frisian area on the North Sea coast.

Later he turned against the Saxon duke and, together with Edzard I, took the city of Groningen, formally on behalf of the Empire but in fact for the benefit of the Cirksena dynasty[1] Uko of East Frisia had one illegitimate son with an unknown mistress: